Why doesn't NetBeans IDE see the generated sources?

Question

I have a Maven-built web-app that uses JPA 2.0 at the back end. The JPA provider is EclipseLink 2.3.2.

When I build the project (and it deploys runs successfully) it builds the JPA meta-model in the directory

${basedir}/target/generated-sources/annotations/

Yet the IDE doesn't see the classes defined there. Little red dots with an exclamation point everywhere. Yet I can navigate to those files in the Projects window and open the generated source files.

Does this happen to anyone else and does anyone know of a way to fix it?

UPDATE:

As a work-around I have discovered that I can exit NetBeans, delete the NetBeans cache directory, then restart. This forces NetBeans to rebuild the cache and then the classes become visible again. Should I submit a bug to the NetBeans bug tracker? I can't come up with a test case to make it happen, but it does fairly often.

Answer 1

If you go to project properties/sources there is a note about this: you need to generate sources under

${basedir}/target/generated-sources/FOOBAR 

where FOOBAR is the name of your plugin.

Answer 2

After reading @jeqo answer, I tested if, by manually renaming:

 "${project.build.directory}/generated-sources/annotations" to ".../generated-sources/hibernate-jpamodelgen" 

would make a difference to Nebeans (I'm using v8.2 on ubuntu 16.04).

Everything worked like a charm.

I then modified the pom file as follows:

1) removed the "org.hibernate: hibernate.jpamodelgen" dependency.

2) configured the maven-compiler-plugin as follows:

   <plugin>
    <groupId>>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.6.1</version>
    <configuration>
      <compilerArgument>-proc:none</compilerArgument>        
    </configuration>
  </plugin>

• These two steps is to make sure that the hibernate-jpamodelgen does not run on auto-pilot just by adding it in the project dependency list. Please refer to JPA Static MetaModel Generator doc.

3) added the following plugin with configuration

  <plugin>
    <groupId>org.bsc.maven</groupId>
    <artifactId>maven-processor-plugin</artifactId>
    <version>3.2.0</version>
    <executions>
      <execution>
        <id>process</id>
        <goals>
          <goal>process</goal>
        </goals>
        <phase>generate-sources</phase>
        <configuration>
          <processors>
            <processor>org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor</processor>
          </processors>
          <defaultOutputDirectory>${project.build.directory}/generated-sources/hibernate-jpamodelgen/</defaultOutputDirectory>
        </configuration>
      </execution>
    </executions>
    <dependencies>
      <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-jpamodelgen</artifactId>
        <version>5.2.9.Final</version>
      </dependency>
    </dependencies>
  </plugin>

This config is directly from the Hibernate JPA Static Metamodel Generator documentation page except for the following line:

<defaultOutputDirectory>${project.build.directory}/generated-sources/hibernate-jpamodelgen/</defaultOutputDirectory>

This line simply generates the metamodel in the directory named after the maven plugin name. From this point, I got all Netbeans references working at design time as if the generated classes were in the src directory subtree.

Hope this helps,

J